Improvement in machines for preparing paving-blocks



Uniti-2n WILLIAM O. ROBBINS AND O. WV. STAFFORD, OF NEW YORK, N. Y.

IMPROVEMENT IN MACHINES FOR PREPARING PAVING-BLOCKS.

Specification forming part of Letters Patent No. 97,553, dated December 7, 1869 antedated November 30, 1869.

.To all 'whom 'it may concern:

Be it known that we, WILLIAM O. ROBBINS and CHARLES W. STAFFORD, of the city and State of New York, have invented, made, and applied to use a certain new and useful Improvemen t in Machinery for Preparing Wooden Blocks for Pavements; and we do hereby declare the following to be a full, clear, and exact description of the said invention, reference being had to the annexed drawings, making part of this specification, wherein- Figure 1 is a general plan of the machine. Fig. 2 is a longitudinal section. Fig. 3 is a cross-section. Fig. 4. is an end view of the cutter-head and cutters for groovin g the block and cutting od the angle. Fig. 5 is a perspective view of one block after it has been grooved on one side. Fig. 6 is a similar view of a block with the dovetail groove on both sides, and Fig. 7 represents a series of blocks united by longitudinal keys to form a section of pavement. y

Similar marks of reference denote the same parts.

The object of this invention is to form in the sides of wooden blocks dovetail grooves, so that ranges of blocks can be secured together by wooden strips and form sections for paving, and the upper angles of the blocks are removed to form grooves in the surface of the pavement when the blocks are laid together, To effect this object the wood to form the pavement isfirst sawed into blocks-by any ordinary means. Then the blocks are fed through our machine, which rst brings them to a uniform thickness, and then t-he dovetail groove is made in one side by the action of critters and the upper angle dressed off, as seen in Fig. 5. The opposite sides of the blocks are grooved, as seen in Fig. 6, when required, by passing them through a similar machine.

Our invention relates to thepeculiarity of construction and mode of mounting the cutters that effect the grooving of the blocks and to the arrangement of mechanism for holding the blocks and presenting them to the action of the cutters.

In the drawings, ot is the bed of the machine, supported upon suitable legs and standing in a horizontall position, as shown; or, to facilitate the delivery of the shavingsand chips,

the bed might stand up vertically, the other parts remaining the same, except the weights that apply pressure to the feeding-rollers.

b b and c c are two pairs of feeding-rollers, the lower ones being level, or nearly so, with the surface of the bed a, the upper ones being supported by sliding boxes and kept toward the other rollers 'by weights or springs. We have shown the levers d, weights c, and slings or links f as the means for giving pressure by the upper rollers to cause the blocks of wood g to be moved forward regularly upon the bed a and between the gages or fences 7L z'. The rollers b b and c c derive their motion from the shaft h', belted to the shaft lo, as shown by red lines in Fig. 2, from which a train of gears, as at l, connects with the lower rollers, and the rollers of each pair b b or c c are connected together, but the upper rollers allowed to rise or fall, and for this purpose gear-wheels are employed upon the shield-plates m m. These devices for giving motion to the pairs of rollers correspond generally with those employed on planing-machines. They therefore form no part of our present invention, and may be of any convenient character.

The rotary cutter u is mounted in a frame that is placed upon the bed a. between the pairs of feeding-rollers. Said cutter is adjusted by the screws u', so that the same can be raised or lowered to adapt the machine to different thicknesses of blocks.

At the side of the cutter u, next the rollers c c, the yielding presser o is fitted, so that the weighted levers o act to force said presser upon the block ofwood and hold it down against the action of the rotary cutters, and the presser p is fitted adjustably upon the other side of the rotary cutter-frame, and these two pressers o and p are sufficiently close to the point at which the rotary cutters operate to effectually hold the block to the hed and prevent the same being raised by the lifting action of the said cutters. This insures a uniform thickness in the blocks of wood that are fed along by the rollers b b and c c, the pressers o and p being closer together than it would be practicable to place the feeding-rollers.. From the presser o the shield 2 rises and turns over the rotary cutter to direct the shavin gs as they are thrown olf, and a similar shield, 3, extends from the 4 down the blocks of wood while being grooved and the angle beveled. The fingers r extend from the presser p, and the lingers s are attached to arms s", that are adjustable in the stocks t. The blocks are pressed by the iingers 5 and 6 as they are moved along through the raceway, so as to keep the bases of the blocks against the fence h.

The tools that we employ for forming the dovetail groove consist of revolving saws or cutters that dress the inclined faces of the dovetail and cutting-tools that take out the intermediate material, so as to leave a smooth groove of the desired sectional shape.

The standard u2 is fitted upon the bed a and provided with a stock, c, that can be raised or loweredA by the screw 8, and this stock 'v is placed at right angles to a plane coinciding with one ofthe surfaces of the dovetail groove, and upon the stock c is a sliding frame, to, carrying the shaft r and cutter-head y and z is a pulley, by means of which the shaft and head are rapidly revolved.

It will now be understood that the stock u can be raised or lowered according to the thickness of the blocks operated upon, and the frame w moved cndwise to adjust the width of groove that is to be out, and a nut and bolt, 9, are employed to clamp them firmly after adiustmeut.

rlhe cutter-head y carries adjustable saw-sections 10, formed to dress off and smooth the sideot` the dovetail groove, and chisels or cutters 1l remove the wood from the middle portion of the groove and smooth the bottoni thereof'.

The standards w3, stock v3, shaft m3, cutterhead @/3, and pulley z3 correspond in construction to those before named, except that the parts are handed or reversed, so as to stand on the opposite side of'the line of blocks and a little to the rear ofthe cutter-head y, and dress oli' and form the other inclined surface of the v dovetail groove.'

the blocks tothe fence hcause the dovetail cutters to act at a uniform distance above the base of the block, so that the keys can be driven in and the bottom surface of thc section will be level.

lu the pavement formed of blocks of wood united into sections by keys introduced into the dovetall grooves it is usual to leave the outsidesurfacesofthesectionssmooth. There fore it will not be necessary to run all the blocks the second time through a machine of the character herein described for forming a second dovetail groove.

What we claim, and desire to secure by Let. ters Patent, is

l. In a machine for dressing and grooving wooden paving-blocks, the combination of the following devices: first, a rotary cutter for reducing the blocks to a uniform thickness; second, mechanism for holding the blocks while being cut; third, mechanism for feeding the blocks through the machine; fourth, cutters for cutting crosswise of the grain of the wood and forming a dovetailed groove in the sides of said blocks; and, fifth, cutters 13 for rcmoving the upper angle ot' said blocks, the parts being constructed, arranged, and operating substantially as and for the purposes set forth.

2. In a machine for grooving wooden paving-blocks, the combination of second, third, and fourth of the beforediamed devices for grooving thc sides of pavement-blocks transy versely of the grain of the wood, substantially as and for the purposes set forth.

In witness whereof we have hereunto set our signatures this 9th day of October, A. D. 1868.

WM. O. ROBBINS. C. W. STAFFORD.

Witnesses:

G11/is. H. SMITH, GEO. D. WALKER. 

